Relief-valve for engine-cylinders.



No. 637,994; Patented Ndv. 2a, |899. A. KLAY.

RELIEF VALVE FOR ENGINE CYLINDERS.

(Application med nu. so, 1899.)

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UNITED STATES PATENT @Erica ANDREV KLAY, OF BLUFFTON, OHIO.

RELIEF-VALVE FOR ENGINE-CYLINDERS.

SPECIFICATION forming part of Letters Patent No. 637,994, dated November 28, 1899. Application led MIUMYBO, 1899. Serial No. 703|859. (No modela To @ZZ 'whom t may concer/2,: p

Be it known that I, ANDREW KLAY, a citizen of the United States, residing at Bluffton, in the county of Allen and State of Ohio, have invented a new and useful Relief-Valve for' piston to allow water of Vcondensation to be blown off and in connection therewith to pro vide a safety-valve adaptedf to be unseated by an excess of pressure in the cylinder to prevent injury to the operating parts.

Further objects and advantages of this invention will appear in the following description, and the novel features thereof will be particularly pointed out in the appended claims.

In the drawings, Figure 1 is a central sectional view of a relief-valve mechanism constructed in accordance with my invention, the parts being shown in their normal relations. Fig. 2 is a similar view showing the parts in the positions which they occupy when subjected to an excess of pressure in the cylinder. Fig. 3 is a detail view of the safetyvalve detached. Fig. 4 is a similar view of the relief-valve detached.

Similar reference characters indicate corresponding parts in all the figures of the drawings.

1 designates a valve-casing provided with a terminal threaded nipple 2, adapted to be seated in the blow-oif opening ofa locomotive or other engine cylinder, said casing having an interior safety-valve seat 3, to which is tted a safety-valve 4t, normally held seated by an operating-spring 5, of which the tension may be varied by means of an adjustable plug 6, threaded in the lower end of the casing, said plug being annular or tubular in construction to provide a passage longitudinally through the casing for the relief of pressure in the cylinder when the safety-valve is unseated. The head of the safetyevalve is cut away or channeled, as shown at 7, whereby while the diameter of the head is such as to tit approximately in the bore of the casing, and thus guide the safety-valve in its movements toward and from its seat, fluid passing through the valveseat is adapted to pass the valve to reach the outlet 8 in the terminal plug. The safetyvalve is also provided with a reduced stem 9, andthe rear or lowerside of the valve-head forms a shoulder against which the seatingspring bears.

The safety-valve, with its stem, is of tubular construction, and the front or upper portion of the channel 10 therein is enlarged or counterbored and is constructed to form a relief-valve seat 11 to receive the relief-valve 12, whereby said relief-valve is housed within the safety-valve. Transverselyspanning the enlarged or counterbored portion of the channel in the safety-valve is a stop-pin 13 to limit the upward or unseating movement of the relief-valve, and said stop-pin is removably fitted in place by means of a threaded shoulder 14 thereof, whereby the removal of the relief valve for purposes of repair or cleansing is facilitated. The relief-valve is provided with a webbed guide-stein 15 to lit in the bore of the safety-valve stem, and thus allow a passage between its sides and said walls of the channel, and bearing against the lower end of the relief-valve stem is an unseating-spring 16, of which the tension may be varied by means of an adjusting-plug 17, threaded in the lower end of the bore of the safety-valve stem, said plug being tubular or of annular construction to communicate with the bore of the safety-valve stem, and thus provide for the escape from the bore of the safety-valve of water of condensation when the relief-valve is unseated.

In operation the relietvalve, which may be termed a low-pressure valve, is normally held unseated by the light unseatingspring employed in connection therewith, and hence during the return stroke of the piston in the cylinder to which the valve mechanism is applied or during the time that said piston is approaching the valve in question water of condensation in advance of the piston may escape through 'the relief-valve seat and thence through the channel of the safetyvalve stem and the opening in the main adjusting-plug (i. The tension of the reliefvalve spring, however, is so small that a slight increase of pressure in the cylinder, as by thev should there be an excess of pressure in the cylinder or a pressure liable to result in injury to the operating parts of the vmachine the safety-valve will be unseated to allow the escape of such excess, and also it will be understood that said safety-valve will be unseated by an excess of water in the cylinder should the relief-valve have failed to allow a complete exhaust thereof. Obviously the tension of the unseating-spring may be varied to offer any desired resistance to the pressure of steam within the cylinder in the seating of the relief-valve, and in the same Way the main or seating spring may be adjusted to have any desired `tension to resist pressure in the cylinder, and thus require any desired cylinder-pressure to unseat the same in opposition to its spring.

An advantage of the above-described construction resides in the fact that the reliefvalve is housed within the safety-valve, the same remaining therein in all of its positions, whereby the entire mechanism occupies the minimum space and accomplishes the desired objects without necessitating any considerable projection beyond the surface of the cylinder to which it may be applied, and in addition to this compactness of construction it will be seen that by the removal of the main plug at the lower or outer end of the casing the safety-valve and the contained reliefvalve may be removed from the casing when necessary fo'r repair or cleaning. It will be understood that a valve mechanism constructed as above described should be arranged at each end of the cylinder in a double-acting engine.

I preferably extend the lower or outer end of the safety-valve stem into the opening of the main adj Listing-plug and provide the walls of the latter with stops 18,'which limit the unseating movement of the safety-valve to avoid straining the seating-spring, and also it will be seen thatl by the arrangement specified the adjusting plug of the unseatingspring may be adjusted to vary the tension of the unseating-spring Without dismounting the parts of the valve mechanism, for the reason that said adj usting-plug of the unseatingspring is accessible through the central opening in the adj usting-plug of the seating-spring.

It will be understood that in practice various changes in the form, proportion', size, and

minor details of construction within the scope of the appended claims may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

Having described my invention, what I claim isl. The combination of a safety-valve having a through longitudinal bore, means for yieldingly holding the said valve seated, a relief-valve housed within and carried by said safety-valve, an unseating-spring therefor, and means carried by the safety-valve for adjusting the tension of said spring, substantially as specified.

2. The combination of a safety-valve having a through longitudinal bore, means for yieldingly holding the said valve seated, a relief-valve housed entirely within the bore of, the safety-valve, an unseating device for the relief-valve and a hollow ad j Listing-plug for said unseating device, substantially as specified.

3. The combination of a valve-casing, a hollow safety-valve seated within said casin g, a valve-seating spring in operative relation with said valve, an annular spring-adjusting plug threadedin the outer end of the casing and adapted for adjustment to vary the tension of the spring', said safety-valve having an axial channel provided at an intermediate point with a relief-valve seat, a relief-valve housed entirely within the channel of the safety-valve, a removable stop-pin transversely spanning said channel in the path of the unseating movement of the relief-valve, an unseating-spring in operative relation with the relief-valve, and a hollow spring-adj usting plug fitted in the outer end of the safety'- valve channel in contact with said unseatingspring, and accessible through the opening of' the first-mentioned plug, substantially as specified.

4:. The combination of a valve-casing, a safety-valve seated therein and having a seating-spring, a centrallyopenadjusting-plug fitted in the casing, said safety-valve having a through longitudinal bore, a relief-valve seated wholly within the plane of the safetyvalve and adapted to close the bore therein, said relief-valve having an unseating-spring,

and an adjusting-plug for said unseatingspring, mounted upon the safety-valve, and accessible, for adjustment, through the central opening of the iirst-named spring-adj usting plug, substantially as specied.

-In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two witnesses.

ANDREW KLAY.

Witnesses:

JOHN ALTHAUS, SAMUEL AMsTU'rz.

IOO 

